Thermostatically-actuated valve



Patented Nov. 9, 1926.

UNITED STATES JOHN J. KENNEY, OF PITTSBURGH, PENNSYLVANIA.-

THERMOSTATICALLY-ACTUATED VALVE.

Application filed December 29, 1924. Serial No. 758,567.

The present invention. relates broadly to valves, and more particularly to snap-action valves of the thermostatic type adapted to control the supply of afluid, such as fuel gas, although the utility of the invention is not limited in ,this..respect.

Valves of this character are generally complicated and therefore expensive to build and easy to get out of order. By the present invention, 1 have provided a construction consisting of a relatively small number of parts and in the preferred form of which the action of the thermostat element is transmitted directly to the valve through a single lever.- I also provide for sufiicient lost motion between' the valve-operating lever and the valve to give the thermostat element a suitable working temperature range within which the Valve will remaineither in its closed or its open position, and at the limits of which thevalve 'will either open or close with a sudden snap-action.

111 the accompanying drawin s:-

Figure 1 is a longitudinal'section through a valve mechanism and its operating thermostat constructed in accordance with a preferred embodiment of my invention;

Figure 2 is a detail sectional view showing thevalve in open position; v

Figure 3 is a detail sectional view on the line IIIIII of Figure 1;

Figure 4 is an elevation of the valveoperating lever;

Figures 5 and 6 are detail views of the pin intermediate the non-expansible member of the thermostat and the valve-operating lever, and

Figure 7 is a detail sectional view similar to Figure 2, showing a modified form of the invention.

Referring to the preferred form of the invention illustrated in Figures 1 and 2, the reference numeral 2 designates the Valve casing having an inlet connection 3 and an outlet connection 4. Intermediate the ports of these connections the casing is provided with a seat 5 for a valve 6, which may be normally urged towards its seat by a spring 7. Access to the-casing is provided by removing the screw closure 8, thereby permitting the parts of the valve mechanism to be removed at will for cleaning or replacing, as may be necessary. The closure has a sleeve 9 and the valve has a cylindrical boss 10 projecting into said sleeve but of slightly smaller external diameter than the internal recess in the face :of the lever 16 op diameter of said sleeve. The spring 7 is located in the sleeve 9 and abuts at one end' against the bottom thereof and at its other end against the top of the boss 10.

Extending rearwardly from the casing is an externally threaded projection 11, whereby the valve casing can be secured to a suitable support. This projection has a bore extending therethrough and through a thickened portion of the wall of the valve casing, and the outer portion of said bore is screw-threaded for the attachment of the tubular expansible member 12 of the thermostat element. Located within the expansible member is the usual non-expansi-ble member 13, which may be of porcelain, for example. The non-expansible member abuts at its outer end against the cap 14 screwed on the outer end of the expansible member, while 'at its inner end it abuts against a separate pin 15 sliding in the bore of the projection 11, which may, if desired, form a gas-tight sealed joint between the interior of the valve casing and the interior of the expansible member 12.

A valve-operating lever 16 -may be-extended vertically in the casing 2 and have a rotatable mounting such as oppositely projecting trunnions 17 adjacent its lower end which bearon' an annular ledge 18 of the thickened portion of the wall of the valve casing. The pin 15 has its inner end beveled to a knife edge which engages in a' shallow transverse groove 19 in the face of the lever 16, said knife edge lying in a horizontal plane slightly above the axis of the trunnions 17. A screw-threaded fulcrum member '20 is adjustably mounted in a screwthreaded bore in the thickened portion of the wall of the casing 2 diametrically opposite the bore in which the pin 15 1s positioned. The fulcrum member has a pin 20 mounted with a loose fit in a socket in its inner end. The pin 20 has a cone-she ed inner end which engages in a shallow conical site theface having the groove 19, the polnt of the pin lying in a horizontal plane slightly below the axis of the trunnions 17. This loose-fitting pin permits the valve-o rating lever to oscillate without causing un ue friction between the trunnions 17 and the seat 1%, and also facilitates assembly without t e necessity of absolute accuracy in machining. The lever 16 has its upper end positioned within the hollow boss 10 of the valve,

and has a cam or inclined recess 21 in said upper end into which extends a teat 22 projecting downwardly from the top of the boss 10. A stud 23 projects from one face of the lever 16 and is arranged a slight distance below the valve 6, and a cooperating stud 24 projects into the interior of the valve casing from the wall thereof. A coil spring '25 is 'mounted. on these "studs and tends to swing the lever in a counter-clockwise direction about the knife edge of the pin 15 as a fulcrum.

When the valve is closed, the normal position of the parts will be as shown in Figure 1. The trunnions 17 resting on the ledge 18 support the weight of the lever 16 and take any downward thrust thereon due to the pressure of the valve on the upper end of the lever. It will thus be seen that the point of the pin 20 and the knife edge of the sliding pin 15 are not subjected to any downward pressure transmitted through the lever 16. Whe'n the expansible member 12 of the thermostat element contracts, the pin 15 is forced to the right, thereby causing the valve-operating lever 16 to rock in a clockwise direction about the point of the pin 20 as a fulcrumfand it will be seen that, due to the relative lengths of the lever arms, a relatively slight movement of the pin 15 will result in a relatively large movement of the upper end of the valve-operating lever. The

first portion of this movement causes the valve to be slid bodily to the right on its seat 5 by. the valve-operating lever until the boss 10 contacts with the side a of the sleeve 9, and prevents any further lateral movement of the valve. Further movement of' the valve-operating lever builds up a gradually increasing pressure between the teat and the cam or incline 21. This condition continues until the pressure is sufficient to overcome the friction between these parts and the action of the spring 7 At this time the valve snaps vertically from its seat and the teat 22 positi'onsitself on the upper end of the lever 16, as illustrated in Figure 2. The valve will. remain in its open position until the desired tem erature has been attained in accordance with the setting of the thermostat element. Any further increase in temperature will then cause such'expansion of the member 12 of the thermostat element as to permit the spring 25 to rock the lever 16 in a counter-clockwise direction about the point of the pin 20 as a fulcrum, said lever forcing the pin 15 into the bore of the projection 11. The first portion of this coun ter-clockwise movement of the lever 16 will result in the valve being bodily moved to the left due to the friction between the teat 22 and the upper end of the lever until the boss 10 engages the left hand side 5 of the sleeve 9 and prevents further lateral movement. Thereafter. further counter-clockwise movemoaova ment of the iever 16 will result in the upper end of the lever 16 being moved relatively to the teat 22, thereby establishing a condition in which the action of the spring in combination with the character of the contacting surfaces between the lever and valve, permits the valve to move bodily to the right as .,viewcd in Figure 1, and downwardly onto its seat with a snap action.

It will be appreciated that the valve when in its closed position, can slide back and forth on its seat, due to the difference between the external diameter of the boss 10 and the internal diameter of the sleeve9, and this is also true when the valve is in open position, as shown in Figure 2. This lost motion is provided in order to allow the valve to remain either in its closed position or n its open position through a suitable workmg temperature range, say about 10- When the valve is closed, it will assume some- The setting of the thermostat can be I changed by adjusting the fulcrum pin 20. To that end, I provide the pin at its outer end with a disk-like head 26 having a han' dle 27,'whereby the pin can be turned. On this disk-like head I have placed an arrow 28 for cooperation with graduations 29 on the outer end of the projection 30. This projection has its outer end screw-threaded to receive a cap 31. By removing the cap 31 the fulcrum pin 20 can be adjusted to the desired position to set the thermostat.

In the modified. construction Shown in Figure 7, the valve 6 has a solid boss 10', the external diameter of which is substantially the same as the internal diameter of Projecting the sleeve 9 of the closure 8. downwardly from the valve is an integral centrally located lug 22', the lower end of which engages the upper surface of a horizontal lever 32 pivoted adjacent the wall of "the valve casing on a pin 33. This lever has an elongated slot 34 through which the pin 33 projects. At its inner end the lever 32 has a downwardl projecting lug 35 providing a cam shoul er 36 between said-lug and the lower surface 37 of the main portion of the lever. The upper end of the valve-operating lever 16 is'rounded at 38 for cooperation with said cam shoulder 36.

In this modified construction, when the expansible memberof the thermostat element contracts and causes the valve-operating lever 16' to swing in a clockwise direction, the horizontal lever 32 is slid to the right by reason of the engagement of the upper end of the lever 16 with the lug 35 until the pin'33 engages the left hand end of the slot 34 and prevents further lateral movement. Thereafter, any further clockwise movement of the lever 16 builds up an effective pressure between the upper end of said lever and the lug 35, which ultimately causes snap action of the valve and movement of the upper end of the lever 16' under the lower surface of said lug.- When the lever 16' moves in a counter-clockwise direction, the horizontal lever 32 is moved to the left until the pin 33 reaches the right hand end of the' slot- 3*l;the valve 6 remaining in open position during such movement of the lever 32. Thereafter, any further counter-clockwise movement of the lever 16 establishes a condition in which the action of the spring 7 in combination with the character of the cam surfaces of the lever 16 and lug 35 permits the lever 32 to move bodily to the right as viewed in Figure 7, thereby permitting the valve to snap to closed position.

Certain advantages of the present invention arise from the provision of a valve of such construction that initially a relatively lost motion is obtained which becomes effective for producing a snap action of the valve in either direction.

Further advantages arise from the simplicity of the construction, the ease of adjustment of the valve, andthe positive character of-the valve movement.

While I have shown and described certain preferred embodiments of my invention, it will be understood that the invention is not limited to the details of construction shown, but that it may be otherwise embodied within the scope oi the appended claims without departing from the spirit of the invention.

I claim .1. In a valve mechanism, a valve casing having a valve seat, a valve cooperating with said seat, a valve-operating lever, a fulcrum member operativel connected with said lever adjacent one en thereof, a thermostat element effective on said lever ad. jacent said end thereof, a spring for moving said lever in opposition to said thermostat element, said valve having a hollow boss into which the other end of said lever projects, said boss having a teat projecting therefrom and said end of said lever having a cam surface cooperating with said teat,-

a sleeve within which said boss projects and having a' greater internal diameter than the external diameter of said boss, and a spring in said sleeve engaging said boss and urging said valve towards its seat, substantially as described.

of two directions, an operating member for said valve having a cam cooperating w1th said operating cam, and means for moving havingan operating cam movable in either of two directions, an operating member for said valve having a cam cooperating with said operating cam, and temperature responsive means for moving said operating member to effect bodily movement of the operating cam first in .one direction and then in another direction, substantially as described.

4. In a valve mechanism, a casing, a valve having an operating cam movable in either of two directions, an operating lever for said valve having a cam cooperating with saidoperating cam, and means for moving said lever to efiect bodily movement of the opcrating cam first in one direction and then in another direction, substantially as described. a

5. In a valve mechanism, a casing, a valve having an operating cam movable in either of two directions, an operating lever for said valve having a cam cooperating with said operating cam, and temperature responsive means for moving said lever to effect bodily movement of the operating cam first in one direction and then in another direction, substanti ally as described.

6. In a valve mechanism, a casing, a valve normally tending to move in one direction and having an operating cam movable in either of two directions, an operating memher for said valve having a cam cooperating with said operating cam, and means for moving said operating member to efi'ect bodily movement of the operating cam first in one direction and then in another direction, substantially as described.

7. In a valve mechanism, a valve casing having a valve seat, a valve cooperating with said seat, a valve operating member, cam sur lot faces between said member and said valve,

and means for moving said member to initially produce simultaneous movement of said cam surfacesand then the relative movement thereof, substantially as described.

8. In a valve mechanism, a valve casing having a valve seat, a valve cooperating with said seat, a valve operatin lever, cam surfaces between said lever and said valve, and means for moving said lever to initially produce simultaneous movement of said cam surfaces and then relative movement thereof, substantially as described.

A 9. In a valve mechanism, a casing, a valve normally tending to move in one direction and having an operating cam movable in either or two directions, an operating memllltl having a valve seat, a valve cooperating with said seat, a valve operating member, cam surfaces .between said member and-said valve,

and temperature responsive means for moving said member to initially produce simultaneous movement of said cam surfaces and then the relative movement thereof, substantially as described.

11. In a valve mechanism, a casing, a

valve having an operating cam movable in either of two directions, an operating member for said valve havingv a cam cooperating with said operating cam, temperature responsive means for moving said operating member to effect bodily movement of the operating cam first-in one direction and then in another direction, and means for varying the temperature at which said temperature responsive means becomes eifective, substantially as described. j

12.-In a valve mechanism, a casing, a valve having an operating cam movable in either of two directions, an operatinglever for said valve having a cam cooperating with said operating cam, temperature responsive means for moving saiollever toefi'ect bodily movement of the operating cam first in one direction and then in another direction, and means for varying the temperature at which said. temperature responsive means becomes effective, substantially as described.

13. In a valve mechanism, a casing, a valve normally tending to move in one direction and having an operating cam movable in either of two directions, an operating member for said valve having a cam cooperating with said operating cam, temperature responsive means for moving said operating member to effect bodily movement of the operating cam first in one direction and then in another direction, and means for varying the temperature at which said temperature responslve means becomes efl'fective, substantially as described.

' 14. In a valve mechanism, a valve casing v having a valve seat, a valve cooperating with said seat, a valve operating member, cam surreoenra temperature responsive means becomes efi'ective, substantially as described.

15. In a valve mechanism, a valve casing having a valve seat,'a valve cooperating with said seat, a valve operating member, means said member and said valve whereby movements of said member are eiiective to operate said valve, one of said cams having an initial limited movement in one direction with the other, and a. limited movement in another direction relative to the other, whereby there is an initial lost motion between the cams in effecting the operation of the valve to one position. 4

16. In a valve mechanism). valve casing having a valve seat, a valve cooperating with said seat, a .valve. operating member, temperature responsive means for moving said for moving said member, and cams between member, and cams between said member and said valve whereby movements of said member are efi'ective. to-operate said valve, one

of said cams having a limited movement with the other in one direction which is ineffectual for operating the valve, and being thereafter movable relatively to the other in another direction for efi'ecting the operation of the valve.

17. In a valve mechanism, a valve casing,

having a valve seat, a valve cooperatingwith said seat, a valve operating member, temperature responsive means for moving said member, cams betweensaid memberand said valve whereby movements of said member are eflective too erate said valve, one of said cams'having a limited movement in the casing with respect to the other cam in one direction, which movement is ineffectual for operating thevalve, and being thereafter movable relatively to the other in another direction for efleeting the operation of the valve, and means for varying the temperature at which said temperature responsive means becomes efl eetive, substantially'as described.

In testimony whereof I have hereunto set my hand.

JOHN J. KENNEY. 

